#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <ctime>
using namespace std;
int n, cnt;
int main() {
	freopen("data.in", "w", stdout);
	int n = 5000;
	cout << n << endl;
	for (int i = 1; i <= n; i++)
		cout << i << " ";
	cout << endl;
	return 0;
}
